Differential vs. single ended reading potentiometer

[maoy]

Hi,

I want to read voltage from a potentiometer powered with the +5V and GND signals from the DAQ board. I have thought of connecting GND output directly to the potentiometer and using single ended mode. Is there any point in using differential mode in this case. If so, should I just connect GND output directly to the AI- input?

Thank you.

[AnalogKid2DigitalMan · Accepted solution]

Single ended should work fine.

-AK2DM

[maoy]

Thanks!

[maoy]

However, I have read that only for signals avobe 1V I should use single ended. My signals go from 0 to 5V.

[Henrik_Volkers]

It's more a question of cable lenght, ground loops, sensor impedance and noise coupling.

If your potentiometer is in a 1k-10k and less than 1m cable in a EMC calm lab, (or all inside a housing) you don't have to worry.

I would add a 100nF (or up to 1µF) from the slider to ground for denoising during slider movement, and add a digital filter..